1. Field of the Invention
The present invention relates to packaging of multiple fluid receptacles, in particular to packaging cuvettes used in a clinical analyzer and a method for inserting cuvettes into an analyzer.
2. Description of the Related Art
Receptacles, such as cuvettes for containing a liquid for analysis or handling, including those having multiple reservoirs, are known in the art as disclosed, for example, in U.S. patent application Publication No. 2003/0003591 A1, Des. 290,170 and U.S. Pat. No. 4,639,135. When cuvettes are used, the cuvettes should be free of contaminates for several reasons. First, when a chemical reaction occurs in the cuvette, the contaminates may taint or interfere with the chemical reaction. Second, particles may interfere with the addition, removal or mixing of fluids by partially or completely obstructing metering devices, such as aspirating nozzles, that could be used for performing such operations. Third, any foreign object in the light path of a measuring device, such as a photometer, may corrupt the measurement by partial obstruction or refraction of the available light. This includes particles within the fluid inside the cuvette, particles adhering to the outside of the cuvette over the read window, and smudges on the read windows, such as fingerprints. Finally, particles may scratch the cuvette read windows during transport. The scratch may then interfere with the photometric or spectrophotometric measurement.
It is known to load multiple cuvettes into an analyzer as disclosed in U.S. Pat. Nos. 4,636,477 and 6,328,164 and as shown in FIGS. 1a-c. The current method of bulk packaging, as shown in the '164 patent and in FIGS. 1a-c, is to fasten the tops of the cuvettes to a flexible support that is coated with an adhesive. As shown in FIG. 1a, cuvettes (10) are adhered to a plastic web (50) by adhesive. Upon insertion of the cuvettes and paper web support into an analyzer, the support is pulled away from the cuvettes leaving the individual cuvettes loaded into the analyzer. The cuvettes are oriented such that the read windows are stacked side by side to face one another. This facilitates some degree of protection to the read window as well as reducing the opportunity for particles to enter the cuvettes. The adhesive used must be strong enough to hold the cuvettes during handling but must cleanly release the cuvette following insertion into an instrument. Several problems with this packaging system includes the cuvettes prematurely separating from the support media (see FIG. 1b), the end cuvettes being unprotected from surface contamination, and the cuvettes not remaining in intimate contact with each other allowing particulates to get between the cuvettes. See FIG. 1c where the packaged cuvettes sag when held by the ends, forming gaps between individual cuvettes.